In many downhole operations, such as fluid sampling and logging operations, various components are equipped with sealing elements to provide a fluid-tight seal between various components, such as string segments, valve components, packer components and sampling components. Sealing elements, such as o-rings, are typically made from elastomer or plastic materials.
When used downhole, such sealing elements are exposed to harsh conditions, which can compromise their performance and result in failure. Types of failure include heat failure, mechanical failure (due to, e.g., stress, abrasion) and explosive decompression. Explosive decompression of O-rings or other elastomers occurs when gas, usually under high pressure and at high temperature, permeates an elastomer downhole over time. Later, if the pressure is reduced too quickly, such as by being brought back to the surface too rapidly, then the gas may not be able to get out quickly enough so the elastomer undergoes explosive decompression. This can result in damage to the O-ring in the form of, e.g., random ruptures, crater-like pores and small slits due to micro-explosions occurring as decompression takes place.